Chassis dynamometers are widely used to test and evaluate the performance of a vehicle. Chassis dynamometers account for transmission losses of the entire drive train and measure the power and other variables at the wheels under various loading conditions. Inertia-type chassis dynamometers effectively measure the transient vehicle output levels by causing a dynamometer roll to accelerate at a rate proportional to the engine output. An addition of a motor/generator may act as a driver to measure drive train parameters during static conditions.
Personal recreational or off-road vehicles are tested on chassis dynamometers, similar to other vehicles, to measure performance and obtain information that will be used in the calibrating the engine and other drive train components. The drive train components are then calibrated, for example, by programming an engine control module. For example, air fuel ratios at specific load points may be optimized by utilizing the information obtained from the dynamometer.
Typically, vehicles such as snowmobiles are tested by driving a single roll or multiple small rolls with the track of the snowmobile, which may be undesirable. Specifically, since there is only line contact between the track and the rolls, the track will slip relative to the rolls especially during hard acceleration. As a result, the vehicle output measured by the dynamometer will be inaccurate.
What is needed is a chassis dynamometer that reduces slipping between the snowmobile tracks and the chassis dynamometer to ensure that more accurate test data is gathered.